Aquaculture farms, particularly in Southeast Asia are
facing severe crisis due to increasing incidences of
White Spot Syndrome Virus (WSSV). Actinomycetes
have provided many important bioactive compounds of high prophylactic and therapeutic value and are
continually being screened for new compounds. In this
communication, the results of a study made to determine
the effectiveness of marine actinomycetes against the white spot disease in penaeid shrimps are presented.
Twenty-five isolates of actinomycetes were tested for
their ability to reduce infection due to WSSV among
cultured shrimps. When these actinomycetes were
made available as feed additives to the post-larvae of
the black tiger shrimp Penaeus monodon for two weeks and challenged with WSSV, the post challenge survival
showed variations from 11 to 83%. However, six
isolates have shown to be the most potential candidates
for further study.

Time-series measurements from a moored data buoy
located in the Bay of Bengal captured signals of inertial
oscillation forced by the September 1997 cyclone. The
progressive vector diagram showed mean northeastward
current with well-defined clockwise circulation.
Spectral analysis exhibited inertial peak at 0.67 cpd
with blue shift and high rotary coefficient of –0.99, which
signifies strong circular inertial oscillation. The wind
and SST also exhibited spectral peak at inertial band
(0.69 cpd) with higher blue shift. The inertial amplitude
of 148.8 cm/s corresponding to a wind stress of 0.99 N/m2
and spectral peak near the local inertial frequency
(0.653 cpd) indicate that the transfer of momentum
was high.

TRMM Microwave Imager (TMI) is reported to be a
useful sensor to measure the atmospheric and oceanic
parameters even in cloudy conditions. Vertically integrated
specific humidity, Total Precipitable Water (TPW) retrieved
from the water vapour absorption channel (22GHz.) along
with 10m wind speed and rain rate derived from TMI is
used to investigate the moisture variation over North Indian
Ocean. Intraseasonal Oscillations (ISO) of TPW during the
summer monsoon seasons 1998, 1999, and 2000 over North
Indian Ocean is explored using wavelet analysis. The
dominant waves in TPW during the monsoon periods and
the differences in ISO over Arabian Sea and Bay of Bengal
are investigated. The northward propagation of TPW
anomaly and its coherence with the coastal rainfall is also
studied. For the diagnostic study of heavy rainfall spells
over the west coast, the intrusion of TPW over the North
Arabian Sea is seen to be a useful tool.

Mann–Kendall non-parametric test was employed for observational trend detection of monthly, seasonal and
annual precipitation of five meteorological subdivisions of
Central Northeast India (CNE India) for different 30-year
normal periods (NP) viz. 1889–1918 (NP1), 1919–1948
(NP2), 1949–1978 (NP3) and 1979–2008 (NP4). The trends
of maximum and minimum temperatures were also investigated.
The slopes of the trend lines were determined using the
method of least square linear fitting. An application of Morelet
wavelet analysis was done with monthly rainfall during June–
September, total rainfall during monsoon season and annual
rainfall to know the periodicity and to test the significance of
periodicity using the power spectrum method. The inferences
figure out from the analyses will be helpful to the policy
managers, planners and agricultural scientists to work out
irrigation and water management options under various
possible climatic eventualities for the region. The long-term
(1889–2008) mean annual rainfall of CNE India is
1,195.1 mm with a standard deviation of 134.1 mm and coefficient of variation of 11%. There is a significant decreasing
trend of 4.6 mm/year for Jharkhand and 3.2 mm/day for CNE
India. Since rice crop is the important kharif crop (May–
October) in this region, the decreasing trend of rainfall during
themonth of July may delay/affect the transplanting/vegetative
phase of the crop, and assured irrigation is very much needed
to tackle the drought situation. During themonth of December,
all the meteorological subdivisions except Jharkhand show a
significant decreasing trend of rainfall during recent normal
period NP4. The decrease of rainfall during December may
hamper sowing of wheat, which is the important rabi crop
(November–March) in most parts of this region. Maximum
temperature shows significant rising trend of 0.008°C/year (at
0.01 level) during monsoon season and 0.014°C/year (at 0.01
level) during post-monsoon season during the period 1914–
2003. The annual maximum temperature also shows significant
increasing trend of 0.008°C/year (at 0.01 level) during
the same period. Minimum temperature shows significant
rising trend of 0.012°C/year (at 0.01 level) during postmonsoon
season and significant falling trend of 0.002°C/year
(at 0.05 level) during monsoon season. A significant 4–
8 years peak periodicity band has been noticed during
September over Western UP, and 30–34 years periodicity
has been observed during July over Bihar subdivision.
However, as far as CNE India is concerned, no significant
periodicity has been noticed in any of the time series.

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Yeasts are ubiquitous in their distribution and populations mainly depend on the
type and concentration of organic materials. The distribution of species, as well as
their numbers and metabolic characteristics were found to be governed by existing
environmental conditions. Marine yeasts were first discovered from the Atlantic
Ocean and following this discovery, yeasts were isolated from different sources, viz.
seawater, marine deposits, seaweeds, fish, marine mammals and sea birds. Nearshore
environments are usually inhabited by tens to thousands of cells per litre of
water, whereas low organic surface to deep-sea oceanic regions contain 10 or fewer
cells/litre. Aerobic forms are found more in clean waters and fermentative forms in
polluted waters. Yeasts are more abundant in silty muds than in sandy sediments.
The isolation frequency of yeasts fell as the depth of the sampling site is increased.
Major genera isolated in this study were Candida, Cryptococcus, Debaryomyces and
Rhodotorula. For biomass estimation ergosterol method was used. Classification and
identification of yeasts were performed using different criteria, i.e. morphology, sexual
reproduction and physiological/biochemical characteristics. Fatty acid profiling or
molecular sequencing of the IGS and ITS regions and 28S gene rDNA ensured
accurate identification.

Aim: To develop a new medium for enhanced production of biomass of an
aquaculture probiotic Pseudomonas MCCB 103 and its antagonistic phenazine
compound, pyocyanin.
Methods and Results: Carbon and nitrogen sources and growth factors, such as
amino acids and vitamins, were screened initially in a mineral medium for the
biomass and antagonistic compound of Pseudomonas MCCB 103. The selected
ingredients were further optimized using a full-factorial central composite
design of the response surface methodology. The medium optimized as per the
model for biomass contained mannitol (20 g l)1), glycerol (20 g l)1), sodium
chloride (5 g l)1), urea (3Æ3 g l)1) and mineral salts solution (20 ml l)1), and
the one optimized for the antagonistic compound contained mannitol (2 g l)1),
glycerol (20 g l)1), sodium chloride (5Æ1 g l)1), urea (3Æ6 g l)1) and mineral
salts solution (20 ml l)1). Subsequently, the model was validated experimentally
with a biomass increase by 19% and fivefold increase of the antagonistic
compound.
Conclusion: Significant increase in the biomass and antagonistic compound
production could be obtained in the new media.
Significance and Impact of the Study: Media formulation and optimization are
the primary steps involved in bioprocess technology, an attempt not made so
far in the production of aquaculture probiotics.

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In Vembanad Lake and its confluent rivers (Kerala, India), the catches of Macrobrachium rosenbergii (de Man) were reported
to have dwindled to a mere 39 t in the 1980s from average landings of 300 t during the 1960s. This decline is due to the impact
of a number of human interventions affecting the ecosystem and, hence, the stocks of M. rosenbergii. Monitoring of landings in
1994-1995 and 1995-1996 indicates an improvement in catches. This paper discusses the reasons for the decline and revival
in stocks and suggestions for their replenishment.

The gel strength, compressibility and folding characteristic of suwari (set) and kamaboko (set and cooked) gels prepared from rohu (Labeo rohita), catla (Catla catla) and mrigal (Cirrhinus mrigala) surimi were examined to understand the occurrence of suwari and modori phenomena in surimi from major freshwater carps. Suwari setting of gels did not take place at lower temperatures. Suwari gels showed good gel strength at 50 °C for rohu and at 60 °C for catla and mrigal after 30 min setting time. Incubation for 60 min decreased the gel strength at 60 °C for rohu and catla. Setting at 25 °C followed by cooking at 90 °C increased the gel strength. Increased setting temperature, however, decreased the gel strength of cooked gels. Gel strength and compressibility data were supported by folding characteristics.

Variations of the infaunal polychates populations due to bottom trawling were studied during December 2000 to November 2002 at depth ranging from 0-50 m along Cochin-Munambam area (Kerala, long. 76degree10'94" to 75degree 56' and lat.9degree58' to 10degree10'), in the southwest coast of India.Infaunal polychaetes from the sediment samples were collected both before and after experimental trawling in order to assess the variations on their abundance (no.m-2),biomass(g.m-2) and diversity due to bottom trawling .Highest variations in polychaetes were recorded at station 9 in May 2002 where polychaete abundance increased to 20710 no.m-2 after trawling from 2787 no.m-2 before trawling.Biomass showed highest variations at station 3 in December 2000 where biomass increased from 7.16g.m-2 recorded before trawling to 34.53 g.m-2 in the samples collected after trawling .Multivariate community analysis carried out based on both species abundance and biomass of plychaetes also confirm the wide variations in the similarities of the stations comparing both before and after trawling